As a framework structure of a vehicle, there is, for example, a framework structure where a reinforcing member is provided between an outer frame and an inner frame in a framework member used for a center pillar. The outer frame of the center pillar includes a long portion that has a substantially U-shaped cross-section and extends in a vertical direction. As the reinforcing member that is provided inside the long portion, a reinforcing member, which has a substantially U-shaped cross-section and extends in a vertical direction, is used.
As this kind of framework structure, in the past, there has been a center pillar structure including a reinforcement. The reinforcement is formed so that a protruding portion, which is formed so as to have a substantially chevron shape toward the outside of a vehicle body, keeps substantially uniform cross-sectional width along the vertical direction (for example, see Patent Literature 1). In this center pillar structure, the protruding portion is formed on the reinforcement so as to have a substantially chevron shape toward the outside of the vehicle body. Accordingly, the vehicle body is stably deformed by an impact, which is applied from the side of the vehicle body, and can absorb the impact.
In the center pillar structure disclosed in Patent Literature 1, the protruding portion of the reinforcement is formed so as to keep substantially uniform width along the vertical direction. Here, since the reinforcement is disposed along the outer frame and the outer frame and the reinforcement are welded to each other, the reinforcement needs to be formed so that the outer shape of the reinforcement corresponds to the inner shape of the outer frame. However, since the reinforcement and the outer frame have a curved shape, it is difficult to form the reinforcement so that the outer shape of the reinforcement corresponds to the inner shape of the outer frame. If the outer shape of the reinforcement does not correspond to the inner shape of the outer frame, there is a possibility that the welding between the outer frame and the reinforcement will be incomplete.
Meanwhile, there is a reinforcement that is shown in FIG. 8 and used for a center pillar. This center pillar includes a reinforcement 50 shown in FIG. 8, and is provided inside an outer frame (not shown) having a cross-sectional shape where one surface forms an open face. The reinforcement 50 includes a plurality of protruding portions 51, which protrudes toward the outer frame, on the surface thereof facing the open face of the outer frame. The protruding portions 51 are disposed at substantially regular intervals in the longitudinal direction of the reinforcement 50 so as to be separated from each other.
Further, the protruding portions 51 of the reinforcement 50 are welded to the outer frame. Since the protruding portions 51 are welded to the outer frame, it is possible to firmly weld the reinforcement 50 to the outer frame without forming the reinforcement 50 with a very high accuracy. Accordingly, the shape of the reinforcement 50 does not require very high accuracy, and this can contribute to the improvement of productivity.